Some of Australia's most popular brands, including Kellogg's and Nestle, have been accused of making food that appeals to children look healthier than it actually is, the Flinders University study shows.Researchers, led by lecturer Kaye Mehte, found 157 products on a major supermarket chain's shelves with packaging designed to appeal to children through the use of cartoons, competitions and give-aways.More than three-quarters of these products were deemed to be unhealthy, because they are high in fat and sugar